Mediterranean Tapeweed Posidonia oceanica (L.) Delile, an Endangered Seagrass Species

THE MOST plentiful and important seagrass in the Mediterranean Sea is Posidonia oceanica L. (Delile) because of its ability to create a three-dimensional habitat with high biodiversity and to build the "matte"(a terrace of interlaced rhizomes and roots trapping sediment). This matte highly influences coast features in terms of wave attenuation and shoreline stabilization. In addition, P. oceanica meadows, which could extend along the coast, from the shoreline until 40m depth, are directly exposed to anthropic pressure coming from the coastal zones and it is particularly sensitive to the environmental conditions. In the last decades, human activities in coastal areas impacted sedimentary processes severely affecting P. oceanica meadows with consequent seagrass loss. This review aims to shed light on the importance of this plant, the extent of its dangerous status, and to urge the international community and governments to try to protect it in all possible ways, especially in Egypt.